gistfile1.txt

[tiffany@arch scripts]$ gcc -shared luajit_test.c -o libluajit_test.so
[tiffany@arch scripts]$ export LD_LIBRARY_PATH=.
[tiffany@arch scripts]$ luajit luajit_test.lua
hello, world
0

luajit_test.c

typedef float test_arr[16];

test_arr global_arr;

int test_fn(test_arr arr) {
  (void)arr;
  printf("hello, world\n");
  return 0;
}

luajit_test.lua

local ffi = require "ffi"
local lib = ffi.load "luajit_test"

ffi.cdef [[

typedef float test_arr[16];

test_arr global_arr;

int test_fn(test_arr arr);

]]

print(lib.test_fn(lib.global_arr));